1. Field of the Invention
The present invention relates to a system and method for providing information to a driver without requiring that the driver remove his eyes from the road. More particularly, the present invention relates to a system and method for providing information such as navigational information such as directional instructions to a driver based on his position and stored information that will allow the driver to travel in the desired direction without requiring that the driver look away from the windshield.
2. Background Art
Driving to an unknown destination or in an unfamiliar location presents the opportunity for a driver to get lost or to miss his turn. Perhaps the driver was looking for a road by a particular name (e.g., “Main Street” or “Harbor Freeway”) and he encounters an intersection without a street sign or with a sign which has another designation (e.g., “Route 1” or “Interstate 5”). The driver does not know whether to turn or drive forward through the intersection, continuing to look for “Main Street” or “Harbor Freeway” because he does not know where Main Street is supposed to be or what the desired intersection is supposed to look like.
Often directions are provided from maps or from verbal instructions without clear and accurate indications as to how far the desired intersection (e.g., “Main Street” or “Harbor Freeway”) is from the present location of his vehicle. Even when an accurate and precise indication of distance is given (e.g., “go 2.7 miles from the origin down Center Street until you intersect Main Street and turn right”), the direction would require that the driver note the initial mileage, calculate the destination mileage of 2.7 miles farther and then observe when the 2.7 miles have passed to find Main Street, an activity which might require frequent calculations and attention to the odometer. Obviously, the driver's looking at the odometer requires the driver to remove his eyes from the road to look at the odometer (instead of the traffic on the road). While a good driver will keep the glances at the odometer to a minimum to allow the greatest attention to be focused on the roadway and its every-changing perils, this presents a distraction.
It would be desirable to have a system of providing directions which allows a driver to enter a destination, then get detailed instructions on how to get there, complete with an appropriate notification of when to turn and which way. Advantageously, these detailed instructions would indicate a necessary turn with an indication provided shortly before the desired turn to allow the driver to concentrate on the driving and the view out the windshield and not on maps or even on a video screen within the car (for example, mounted on the console of the vehicle in the case of a system provided by Hertz and called the “NeverLost” system or in similar navigational aids provided by auto companies such as General Motors). The Hertz NeverLost system includes a route set on a console unit which is used to show messages about turns on the console unit, with a tone indicating that a message has been displayed on the console. However, the console is located away from the windshield and looking at the console requires the driver to remove his eyes from the road.
Anything which distracts the driver's eyes from the road presents a risk of collision or leaving the road. So, if the driver must watch the odometer to know when his turn is expected, he can not be watching the road at the same time. Similarly, if the driver is looking at a map or a display on the console, the driver can't be simultaneously looking at the road.
If, for any reason, the driver should miss a turn, the sooner the driver is alerted to the fact that the turn was missed, the easier and quicker the driver may be able to recover from the mistake.
It would also be desirable to have a system where the driver receives multiple advisory alerts or warnings of an upcoming turn at different distances from the turn and it would be desirable if the advance notice was related to the speed at which the vehicle is approaching the turn. That is, an indication of a turn 100 feet in advance may be adequate where the vehicle is traveling 5 miles per hour (or about 7 feet per second), but an indication of the turn 100 feet in advance of the turn while the vehicle is traveling 70 miles per hour allows only a one second advance notice before the turn, while turning may require more than the second just to decelerate. Accordingly, it would be desirable to provide a notice of a turn at one or more relatively fixed time intervals before the turn (perhaps 15 seconds and 5 seconds before) rather than a predetermined distance before the turn, rather than a fixed distance before a turn. Since the use of location alone provides only the distance, it is necessary to combine the location information with speed information to provide an alert which is based on calculated time to the turn, but this is accomplished using speed information. Speed information can be calculated from past geographic positions or can be obtained from a connection to the vehicle (the speedometer or changes in the odometer).
The description of the present invention which follows is based on a presupposition that the reader has a basic knowledge of global positioning systems and of stored maps which are available over the Internet. Such global positioning systems can provide the present position of a sensor (for example, a sensor mounted within a vehicle) to a very accurate location (perhaps within 10 feet). The positioning information can be stored and used to plot the progress of a vehicle over time by noting the position of the vehicle at successive time intervals. Such a system would allow for the plotting of the circular ramp of a freeway interchange and the calculation of the location of the interchange and the radius of its curvature. Stored maps exist for most cities and main routes between cities and can be accessed in a variety of ways, such as from the Internet from one of a variety of web sites or from map software which is commercially available. These maps can be used for detailed driving instructions by entering a starting location and a desired termination, providing even a listing of the necessary turns and the mileage along each leg of the journey.
Some prior art systems have been proposed which provide driving instructions on a video screen provided in the center console. Such a system has the undesired requirement of periodically requiring the driver's looking at the video screen rather than on the road ahead.
Prior art systems for providing driving instruction in the form of a printed sheet of paper, indicating that the first road is to be taken for 2.7 miles, then turn right on Main Street for 1.6 miles, then turn left (and so forth). The providing of a separate piece of paper with directions also requires that the driver look at the separate piece of paper rather than the road, and the printed sheet of paper does not provide an indication when the desired road is being approached.
Prior art systems exist where a map is provided are similar to those providing a printed sheet of paper. It has the same disadvantages of not providing any indication when the desired road is being approached and in requiring that the driver's attention is diverted from looking at the road to looking at the map.
Thus, the prior art systems have undesirable disadvantages and limitations.